1. Field of the Invention
The present invention relates to an improved sheet binding apparatus and particularly to a thermal sheet binding apparatus for simultaneously binding sheets in one or more folders provided with a heat-sensitive binding agent. Furthermore, the present invention relates to a method for an automatic binding process having no requirement for manually operated temperature and time intervals.
2. Description of the Prior Art
To avoid some drawbacks with older binding technniques, such as uncertainty in judging the length of time to be set for obtaining proper binding, a new technique was presented by the present applicant through his U.S. Pat. No. 4,367,116 "Binding Apparatus". By the new technique the heating element is continuously heated for maintaining a desired working temperature. Since the binding apparatus presented was designed to take care of folders of different thickness by having an adjustable opening, there was a demand for different operation times dependent on the actual binder or folder thickness. This was solved by having a set of buttons for presetting of the operating time.
The binding apparatus according to the U.S. patent mentioned is simple to operate but has an undesirable energy consumption. Though the operation is simple it would be better if one could also avoid the time presetting operation. These targets are obtained by the present invention.